Anyone remember this book and its companion, Men Hunting Things? What I am really looking for is a short story I read about 20 years ago.

Plot:

Peaceful Earth gets a signal from space that turns out to be a powerful battlecruiser. Captain of said is very apologetic saying they are chasing a horrible dangerous planet wrecking creature in another ship that is headed Earth's way. They beam pictures of the creature and its destruction to Earth and advise that the planet prepare its defenses.

The US tracks the horrible creature's ship as it lands on a small Caribbean island, while the crew of the battlecruiser skidaddle, saying sorry this will be too horrible for us to watch – its your problem now. The US sends a task force that is going to nuke the island, but finds out at the last second there is a small scientific team on the island.

Cut to the science team, who having heard a warning to evacuate the island, are trying to board a boat. Their cat gets loose and starts hissing and spitting and runs off into the jungle, where they hear a horrid cat-fight. Moments later the cat returns, dragging along something dead, which turns out to be the horrid creature – it is only about 18" tall.

The last scene is some sort of radar plotting area where they go "Sir, that alien ship – it was only like 3 yards long.

I don't know whether this is connected, but there's a 1950s sci-fi radio show (Dimension X episode, I think) about alien invaders, who get in radio communication with a crackpot inventor, who tries to arouse Earth's defenses (unaware the aliens are homing in on his signal), only to have the alien ship crash and it's about the size of a pie plate.

And in Katherine Wilhelm's "Pictures Don't Lie", the aliens who have sent us soap operas and other information arrive at the designated redenzvous on Earth with the scientists and the military, and find themselves in a lake – when they were supposed to land at a desert airfield – under assualt from 'huge, pulpy monsters' who destroy the ship and crew.

Despite all the clues, the scientists are dumbfounded and want to know where the alien craft wreck is and plan to set out to find it. The Colonel in charge, understadning photographic scale, comments "We'll need a microscope to do that."